1. Field of the Invention
This invention relates to a blood circulation assisting apparatus, and more particularly to an intraaortic balloon catheter with a blood feed passage formed therein for assisting blood circulation.
2. Description of Related Art
As a circulation assisting method for treating cardiogenic shock due to acute cardiac infarction, artificial cardiopulmonary withdrawal, a low output failure symptom after open heart surgery, and various types of heart failure appearing in emergency medical care, intraaortic balloon pumping (hereinafter referred to as "IABP") is generally used, in order to reduce afterloads on the heart and increase the amount of blood flowing through the coronaria to thereby restore the cardio function. Actually, however, there are many serious cases in which cardiac function cannot easily be restored by simply using the IABP. Recently, improved medical care results have been obtained in such serious cases, using both the IABP and a percutaneous cardiopulmonary support (hereinafter referred to as "PCPS). The PCPS is a simple cardiopulmonary assisting unit which comprises a centrifugal pump, an artificial lung, a blood intake passage and a blood feed passage. In this unit, the blood pulled by the blood intake passage is subjected to gas exchange, and then guided to the blood feed passage.
Although the use of both the IABP and the PCPS exhibits an excellent circulation assisting effect, it is disadvantageous in light of long-term prognosis, since it may well cause sequela such as hypoxic encephalopathy after the heart failure is remedied. In the case of using the conventional femoral arterial blood feeding method, the blood into which oxygen is sufficiently introduced by the PCPS is hard to circulate through the brain. This difficulty is considered the reason why the hypoxic encephalopathy cannot be eased.